strange shadows and artifacts on cycles render
It looks like you are having duplicated meshes intersecting each other on your mesh, if not then it should be normals that are not represented correctly. Try to removing double and recalculate your normals and see if it helps. Also select all your face and apply smooth shading.

Attaching a portion of your mesh would let us help you diagnose the issue too. You could just leave the nose portion in the file where the artifact is showing up.

Preliminary Probe

Probing into the file, I found that you have meshes that have all the edges "mark as sharp"
to unmark the meshes. Go into edit mode, select all the edges ... hit CtrlE and select "Clear Sharp".

After which, I also found out that your faces are not joined as a single mesh ... to solve that.
Do this ... With all the faces selected , Hit W select "remove doubles". This will weld all the triangles into a single mesh and remove vertices that takes up the same 3d space.

At this point I apply "shade smooth" with the W "special meun. This mess up the normals. Then I proceed to add a modifier "Normal Edit" under then modify column. The strange shadows are gone but some harsh edges still persist.

Solution



Note
You can read about why this happens here. http://www.blenderartists.org/forum/showthread.php?370090-Cycles-Glass-render-Black&amp;p=2864146&amp;viewfull=1#post2864146